1. Field of the Invention
The present invention relates to a shaft-sealing device having an inner modular structure for combining with a rotary machine. Particularly, the present invention relates to the shaft-sealing device having the inner modular structure for combining with the rotary machine mechanically connected to a pump system or the like. More particularly, the present invention relates to the shaft-sealing device having the inner modular structure to permit preassembling the shaft-sealing device so as to speed up installation time.
2. Description of the Related Art
In general, a conventional rotary machine such as a pump system includes a shaft sealing structure for sealing liquids such as cooling fluid. The shaft sealing structure consists of several parts. In assembling operation, each of the parts of the shaft sealing structure must be manually installed one by one within an inner space formed between a shaft hole and a rotary shaft. This practice necessitates a precise installation and unavoidably becomes disadvantageous particularly in case of imprecise installation. Furthermore, it is difficult and inconvenient to construct compactly the parts of the shaft sealing structure one by one between the shaft hole and the rotary shaft where an installation space is limited.
One type of conventional shaft-sealing device is disclosed in applicant own Taiwanese patent publication No. 454,827, entitled “SHAFT-SEALING DEVICE FOR A ROTARY MACHINE.” TWN No. 454,827 discloses a shaft-sealing device including a shaft tube, a positioning sleeve, a first sealing ring unit, a main body, a second sealing ring unit and a fixed sleeve. Each of the first sealing ring units essentially consists of a rotary ring and a fixed ring. Sealing parts of the shaft-sealing device disclosed in TWN No. 454,827 are successively assembled on a rotary shaft to receive within a shaft hole.
Another type of conventional shaft-sealing device is disclosed in another applicant own Taiwanese patent publication No. 454,839, entitled “SHAFT-SEALING DEVICE FOR A ROTARY MACHINE (2).” TWN No. 454,839 also discloses a shaft-sealing device including a shaft tube, a positioning sleeve, a rotary ring, a fixed ring, a main body, a sealing ring unit and a fixed sleeve. Sealing parts of the shaft-sealing device disclosed in TWN No. 454,839 are successively assembled on a rotary shaft to receive within a shaft hole.
However, the rotary rings and the fixed rings of the shaft-sealing devices of TWN Nos. 454,827 and 454,839 are connected with each other by positioning pins within positioning holes that may complicate and increase manufacture cost. Since the structure of the positioning pins, in long-term use, may be weakened, the rotational movement of the shaft sealing device is not smooth, particularly, in high-speed rotation.
Another applicant own Taiwanese patent publication No. 459,938, entitled “SECTIONAL SHAFT-SEALING DEVICE FOR A ROTARY MACHINE USE,” also discloses a shaft-sealing device. The shaft-sealing device includes a shaft tube, a first rotary ring unit, a first sealing ring unit, a main body, a second rotary ring unit and a second sealing ring unit. The shaft tube is securely connected with a rotary shaft of the rotary machine and rotated therewith. In assembling operation, the first rotary ring unit is securely mounted on and rotated with a first end of the shaft tube on which further providing with an annular end flange for retaining the first rotary ring unit. The first sealing ring unit is engaged with the first rotary ring unit, and also securely mounted on a predetermined position of the shaft tube which is proximate to a shaft hole of the rotary machine. The main body such as an outer lid is securely connected with the rotary machine, and used to engage with the first sealing ring unit. The main body includes an annular wall essentially delimiting an inner assembling space. The second rotary ring unit is securely mounted on a second end of the shaft tube beyond the rotary machine, and received in the inner space of the main body. The second sealing ring unit is securely mounted on a predetermined position of the shaft tube beyond the annular end flange of the main body, and disposed outside the main body.
The parts of the shaft-sealing device disclosed in TWN No. 459,938 must be assembled and examined in a leakage test prior to installing the shaft-sealing device on the rotary machine. The shaft-sealing device can be applied to the rotary machine if no leakage of cooling fluid occurs in a test. The leakage test can consequently avoid a disassembling or reassembling operation for the shaft-sealing device after installing on the rotary machine if leakage of cooling fluid occurs in use. Although the positioning member connected the end of the shaft tube with the first rotary ring of No. 459938 may increase intensity of the entire structure, it still complicates the entire structure and increases manufacture cost.
The present invention intends to provide a shaft-sealing device having an inner modular structure to permit preassembling the shaft-sealing device so as to speed up installation time in such a way to mitigate and overcome the above problem.